Method for manufacturing waterproof zipper and the device manufactured from the same

ABSTRACT

A method for manufacturing a waterproof zipper comprises steps of: feeding a nylon zipper to a feeding device; passing the nylon zipper to a gluing device and coating PU gel on backsides of the fastener strips of the nylon zipper; adhering a PU film with PU gel on backsides of the fastener strips by using rollers to press the PU film so as to be formed as a waterproof layer; wherein the PU film is adhered on a release paper; heating the PU film and PU gel to be formed as a waterproof layer; cutting the waterproof layer along a center of the waterproof layer so as to form with two waterproof layers are located at the two fastener strips. Thus a waterproof zipper is formed. Finally, the waterproof zipper is guided out. A nylon waterproof zipper is made by using method.

CROSS REFERENCE TO RELATED APPLICATION

This is a divisional application Ser. No. 10/734.912, filed Dec. 9, 2003 now a pending application is divided by products in its entirety herein.

FIELD OF THE INVENTION

The present invention relates to waterproof zippers, and particularly to a method for manufacturing a waterproof zipper and the device made from the same.

BACKGROUND OF THE INVENTION

In the prior art of manufacturing slide fastener, it is found that the slide fastener can be immersed in repellant liquid so that mist will not be absorbed by stringer tapes easily. However, the result cannot be maintained for a longer time. When it is flushed by large amount of water, the stringer tapes always exposes in the steam, the waterproof effect will be reduced.

In Taiwan Patent Publication No. 094285, published on Dec. 16, 1987, “an impermeable water proof slide fastener”, applied by Japanese YKK CO., a flexible plastic membrane with the stringer tapes is heated and sealed for resisting water seepage. However, this prior art still needs improvement. It needs a C type slider to slide along the gripper elements to protect them from moisture. The bond needs to be detached from the stringer tapes due to long time abrasion. The adhesive of the bond between stringer tapes and membrane would have been diminished.

In Taiwan Patent Publication No. 126351, published on Jan. 6, 1990. “water proof zipper” applied by Japanese YKK Co. disclosed a prior art, where in manufacturing slide fasteners, water-absorptive swollen material Lanceal-F must be incorporated into nylon gripper elements. Then the nylon gripper elements with Lanceal-F is seamed on the stringer tapes. This prior art needs more labors and costs than other ways of manufacturing.

In another Taiwan Patent Publication No. 503715, published on Sep. 21, 2002. “liquid impermeable slide fastener” also applied by Jap. YKK Co. In this prior art, a special kind of slider instead of the popular coupling slider is used, but this special slider can not be matched with other sliders and thus can not be widely used.

Moreover, in U.S. Pat; No. 6,105,214 patent, “water proof slide fastener and process for preparing the same” assigned to Stuart Press on Aug. 22, 2000. The characteristics of the invention are a water resistant slide fastener, including a pair of stringer tapes each having first and second opposed surfaces and each having a series of gripper elements positioned along edges of said first surface; and a water resistant layer on said second surfaces, wherein said water resistant layer has an adhesion to said stringer tapes of at least about 6 lb/in. Thus, a combined multi-layer film adheres to the surface of stringer tapes. As they oriented outward to bear the abrasion or impact directly, they will be damaged. The water proof effect is reduced.

In U.S. Pat. No. 6,427,294 “water proof slide fastener and manufacturing method thereof assigned to YKK Co on Aug. 6, 2002, disclosed a multi-layer film laminated to the stringer tapes. Providing a waterproof slide fastener in which a synthetic resin film is fused to a fastener tape in order to prevent a perforation phenomenon that the synthetic resin film does not exist locally. A laminated synthetic resin film composed of low melting point resin layer having melting point of, for example, 100-140° C. and high melting point resin layer having melting point of, for example, 150-230° C. is fused to a surface or both surfaces of a pair of the fastener tapes with the low melting point resin layer being in contact with and opposing the fastener tape by heating with pressure. Fastener elements are mounted onto a side edge of the fastener tape and the laminated synthetic resin film is formed so as to protrude outward from the side edge of the fastener tape and a center point of coupling of the fastener elements. Because the high melting point resin layer disposed on the surface of the fastener tape is not melted, no perforation phenomenon occurs. Further, because the laminated synthetic resin film protrudes from the side edge, waterproof function is secured.

The various objects and advantages of the present invention will be more readily understood from the following detailed description when read in conjunction with the appended drawing.

SUMMARY OF THE INVENTION

Accordingly, the primary object of the present invention is to provide a method for manufacturing a waterproof zipper comprising steps of: (a) feeding a nylon zipper to a feeding device; (b) passing the nylon zipper to a gluing device and coating PU gel on backsides of the fastener strips of the nylon zipper; (c) adhering a PU film with PU gel on backsides of the fastener strips by using rollers to press the PU film so as to be formed as a waterproof layer; wherein the PU film is adhered on a release paper; (d) heating the PU film and PU gel to be formed as a waterproof layer; (e) cutting the waterproof layer along a center of the waterproof layer so as to be formed with two waterproof layers which are located at the two fastener strips; and thus a waterproof zipper being formed and (f) guiding the waterproof zipper out.

Another object of the present invention is to provide a nylon waterproof zipper comprising two symmetric fastener strips; each fastener strip has a front surface and a back surface; an inner side of the front surface of each fastener strip having a cord thread protruded from the surface; two chains being mounted along the cord threads, respectively; the cord threads being fixed to the fastener strips, respectively; the two chains being engaged by a coupling slider; a back surface of each fastener strip being combined with a thin waterproof layer; characterized in that: a back surface of each fastener strip is permeated with PU gel; and then a PU film is adhered to the back surface by thermal plastic stage so as to be formed as a waterproof layer which includes an inner layer of the PU gel permeating into the fastener strips and an outer layer at an outer side of the fastener strips.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view of the waterproof zipper of the present invention.

FIG. 2A is backside perspective view of the waterproof zipper of the present invention.

FIG. 2B is a backside perspective view of the waterproof zipper of the present invention, wherein the zipper is patterned.

FIG. 2C is a backside elevation perspective view of the waterproof zipper with patterns.

FIG. 3 is a block diagram of the first stage of the first embodiment of the present invention.

FIG. 4 is a manufacturing flow diagram of the first stage of the first embodiment of the present invention.

FIG. 4A is a cross sectional view showing the nylon zipper of the present invention.

FIG. 4B is a cross sectional view showing the nylon zipper added with PU gel.

FIG. 4C is a cross sectional view showing that the PU gel is permeated into the fibers of the fastener strips of the present invention.

FIG. 5 is a manufacturing block diagram of the second stage of the first embodiment of the present invention.

FIG. 6 is a manufacturing flow diagram of the second stage of the first embodiment of the present invention.

FIG. 6A is a cross sectional view showing the nylon zipper of the present invention.

FIG. 6B is a cross sectional view about the nylon zipper with PU film in the present invention, where the PU film is combined with PU gel.

FIG. 6C is a cross sectional view about the nylon zipper of the present invention, where the nylon zipper is combined with a waterproof layer by thermal plastics, and the PU film is combined with PU gel.

FIG. 7 is a block diagram for the manufacturing stage in the second embodiment of the present invention.

FIG. 8 is a flow diagram about the manufacturing stage of the second embodiment of the present invention.

FIG. 9 is a block diagram about the manufacturing stage of the third embodiment of the present invention.

FIG. 10 is a flow diagram about the manufacturing stage of the third embodiment of the present invention.

FIG. 11 is a block diagram about the manufacturing stage of the fourth embodiment of the present invention.

FIG. 12 is a cross sectional view about the nylon zipper of the present invention after screen printing.

FIG. 13 is a cross sectional view about the nylon zipper of the present invention after press-printing.

FIG. 14 shows the appearances of the samples of the present invention and the prior art are boiled in water.

FIG. 15 shows the appearances of the samples of the present invention and the prior art are sunk in organic solvent.

FIG. 16 shows the waterproof zipper of the present invention has two printed patterns.

DETAILED DESCRIPTION OF THE INVENTION

In order that those skilled in the art can further understand the present invention, a description will be described in the following in details. However, these descriptions and the appended drawings are only used to cause those skilled in the art to understand the objects, features, and characteristics of the present invention, but not to be used to confine the scope and spirit of the present invention defined in the appended claims.

Referring to FIG. 1, the nylon waterproof zipper 10 of the present invention includes two symmetric fastener strips 11, 12. Each fastener strip has a front surface and a back surface. An inner side of the front surface of each fastener strip 11, 12 has a cord thread 13, 14 protruded from the surface thereof. The chains 15, 16 are mounted along the cord threads 13, 14, respectively. The cord threads 13, 14 are fixed to the fastener strips 11, 12, respectively. Two chains 15, 16 are meshed with a coupling slider.

Referring to FIG. 2A, the back surfaces of the fastener strips 11, 12 are illustrated. It is illustrated that the cord threads 13, 14 and chains 15, 16 are hidden in the fastener strips 11, 12. Each back surface is combined with a thin waterproof layer 17, 18. After engaging the chains 15, 16 closely, the waterproof layers 17, 18 have the effect of waterproof so that water will not drain into the fastener strips 11, 12.

First Embodiment

In this embodiment, the performance is described in two stages. FIG. 3 shows the first stage and FIG. 5 shows the second stage. At first, referring to FIG. 3, the first stage includes the steps of feeding material 21, gluing 22, pressing 23, drying 24, and outputting 25.

As shown in FIG. 4, in the feeding stage 21, the nylon zipper 10 passes through a feeding device (formed by an upper and a lower rollers 32, 33) and is taken out from the feeding tank 31 so that the nylon zipper 10 is extended properly to be in flat state. The cross section view thereof is shown in FIG. 4A.

Next, a gluing step 22 is performed. In this step, the fastener strips 11, 12 are gluing so that the back sides of the fastener strips 11, 12 are coated with a layer of high adhesive gel. The main component of the glue is di-thermal liquid bridging polyester urine resin (i.e., PU gel) mixed with bridging agent. The gluing device is made of a gel storage tank 34 with a gluing roller 35 therein. A pressing roller 36 with a rotation direction opposite to the gluing roller 35 is installed at one side of the nylon zipper 10 opposite to the gluing roller 35. When the gluing roller 35 is adhered with PU gel 37 in the gel storage tank 34, the pressing roller 36 presses the fastener strips 11, 12 so that the PU gel 37 is transferred to the back sides of the fastener strips 11, 12 and is combined to the polyester fibers. The cross sectional view of the gluing nylon zipper 10 is illustrated in FIG. 4B. The PU gel includes PU adhesive and solvent. If material of the fastener strips are changed the gel can be replaced by other adhesives.

Next, a pressing step 23 is performed. When the fastener strips 11, 12 passes through the pressing rollers 38, 39, the PU gel is pressed into the polyester fibers of the fastener strips 11, 12. The capillary is helpful to the addition of the gel by pressing without increasing the thickness of the fastener strips 11, 12. Meanwhile, a good combining force is generated. At this time, the cross sectional view of the nylon zipper 10′ is illustrated in FIG. 4C. Besides, the pressing rollers 38, 39 have further function of extending and smoothing the fastener strips 11, 12 with the guide rollers 41, 42 for drying.

In drying step 24, the fastener strips 11, 12 are heated in the heating box 40 so that solvent of the PU gel 37 vaporizes. The temperature of the drying box is about 120-180° C. The heating time is determined by temperature, for example, about 12 seconds in 150° C.

Finally, the guiding step 25 is performed. In the guide device formed by the rollers 41, 42, when the active roller 41 rotates, the fastener strips 11, 12 will be driven so as to output the nylon zipper 10 coated with PU gel. Besides, the two rollers move speedily with a pull force for adjusting fastener strips 11, 12.

In above stages, the first stage can be repeated 1 to 3 times for increasing the coating and adhering effect between the PU gel 37 and the fastener strips 11, 12. This is related to the combining effect of the second manufacturing stage and PU gel 37.

With reference to FIG. 5, the block diagram of the second stage of the present invention is illustrated. Moreover, FIG. 6 shows the flow diagram of the second stage. From FIG. 5, it is shown that the stage includes the steps of feeding 26, adhering 27, heating and extruding 28, cutting 29 and guiding 30.

In above feeding step 26, the nylon zipper 10 coated with PU gel 37 are driven by two rollers 44, 45 and then are taken out from the feeding tank 43. The nylon zipper 10 is extended properly. The cross sectional view of the structure of the nylon zipper 10 is illustrated in FIG. 6A.

Next, the adhering step 27 is executed. A compound film formed by a release paper 50 and PU film 51 is wound along a winding roller 46. The width of the film is equal to that of the nylon zipper 10 coated with PU gel 37. When the compound film and nylon zipper are pressed by the rollers 47, 48, the PU film 51 is tightly adhered to the PU gel 37 at the backside of the fastener strips, as shown in FIG. 6B. Furthermore, the release paper 50 of the film is separated from the PU film 51 behind the roller 47, then separated release paper 50 guided out by another roller 49. Generally, the thickness of the PU film 51 is about 2-5 mm, which can be increased based on the manufacturing conditions. The PU film 51 is a single layer film. It is especially suited for batch production with a variety of types of different colors. Besides, the pigment can be added in the manufacturing of the film for getting the desired colors. If no pigment is added, agents for preventing change of color or yellowing can be added for getting a transparent PU film. Moreover, anti-freeze agent, anti-acid agent, anti-alkali agent, anti-hardening agent, etc. can be added. Moreover, since the coarseness of the surface of the release paper is not uniform, when it is separated from the PU film 51, the inner surface of the PU film 51 may be coarse or smooth. If it is a coarse surface, the waterproof layer has a dim surface. If it is smooth, the waterproof layer is bright. In other words, a bright surface is transparent, and the dim surface is semi-transparent.

Then, the heating step 28 is executed. Mainly, the nylon zipper 10″ adhering on the PU film 51 is transferred to a heating box 52 to be heated in a temperature of 120-200° C. through 12-17 seconds so that the PU film 51 is combined with the PU gel 37 by thermal plastics (referring to FIG. 6C). Since the PU film 51 and PU gel 37 are main components, after overheating, they are provided as plasticizer on the compatiblility of the zipper and then they are combined. Furthermore, a rear end of the heating box 52 may be installed with an extruding device formed by an upper press roller 54 and a lower press roller 53. The rollers presses the zipper 10 so that the backsides of the fastener strips 11, 12 are formed with waterproof layers 17, 18. Since the adhesion of the waterproof layers and the fastener strips 11, 12 are concrete, the two are firmly secured.

Next, the cutting stage 29 is performed. A thin knife 55 between the two fastener strips 11, 12 cut the moving PU film 51 through the median line thereof so that the original single sheet waterproof layer is cut into a left waterproof layer 17 and a right waterproof layer 18 (referring to FIG. 2A). The cutting depth can be determined by the thickness of the PU film 51. Since the waterproof layer cut by the cutting knife 55, so general sliders can be adapted to the well-formed zipper after it is finished. There is no need to design a special kind of slider for the zipper products of the present invention.

Finally, a guide device formed by a set of upper and lower rollers 56 and 57 are used in the guide step 30. The roller 56 is a driving wheel and the roller 57 is a driven roller. The driving wheel 56 rotates to drive the fastener strips 11, 12 so as to output the nylon zipper 10 with waterproof layers 17 and 18 at the backside thereof. Besides, the two rollers 56, 57 have the function-of adjusting the pull force and speed of the fastener strips. Furthermore, when a distal end of the heating box 52 is installed with two press rollers 53, 54, the rollers 56, 57 can be used to replace the two press rollers 53, 54 for pressing the PU film 51, PU gel 37 and the fastener strips 11, 12 so as to have an optimum effect.

Above mentioned is one preferred embodiment of the present invention for describing the present invention in detail, however, some modified embodiments within the spirit of the present invention can be used without confine the scope of the present invention. For example, in the first stage, the feeding step 21 and the gluing step 2 with a preheat step (not shown). Thereby, the unglued zipper 10′ is preheated in temperature between 70-120° C. Thereby, the unglued nylon zipper 10′ is more suitable to be adhered to the PU gel 37. In other words, heated unglued nylon zipper 10 has a preferred adhesion coating effect to the PU gel 37.

Moreover, in the second step 22, other adhesive combinable to the PU film 51, such as base material polymer (polyester polyol or acrylic acid polyol) or micro inorganic stuff agent) which is formed by bridging and hardening). Thereby, it is not confined to above said PU gel 37.

Further, in second stage, the heating box 52 can be changed as many sets of heating and pressing rollers necessary. Besides, a plurality of press rollers or a plurality of heating sections can be used in the present invention so that the PU film 51, PU gel 37 and fastener strips 11, 12 have an optimum combining effect.

Second Embodiment

In this embodiment, the first and second manufacturing stages are integrated as a continuous production line, as shown in FIGS. 7 and 8. The steps are feeding step 21, gluing step 22, pressing step 23, drying step 24, adhesion step 27, heating step 28, cutting step 29, guide step 30. In this embodiment, the guide device 25 in the first step and the feeding step 26 in the second stage can be reduced.

Third Embodiment

To simplify the manufacturing lines in FIGS. 7 and 8, the block diagram in FIG. 9 can be performed. The stages includes the step of feeding step 21, gluing step 22, adhesion step 27, heating step 28, cutting step 29 and guide step 30, as shown in FIG. 10. In this embodiment, not only the manufacturing stage is simplified, but also a batch of small amount in manufacturing can be performed easily. From above description, it is known that the embodiments in FIGS. 9 and 10 are basic and simple manufacturing method in the present invention.

Fourth Embodiment

In above mentioned three manufacturing method, a printing step 221 or a press step 222 is added between the gluing step 22 and the adhesion step 23 (referring to FIG. 11). In the printing step 221, the inner surface of the PU film 51 (not outer surface) is printed with beautiful pattern 512 (referring to FIG. 12) by screen printing. If it is presented by a perspective view, as shown in FIG. 2B, and practical view is illustrated in FIG. 16. In the press step 222, the convex or concave textures are printed on the inner surface (not outer surface) of the PU film 51 to form textures 513 (referring to FIG. 13). A perspective view is illustrated in FIG. 2C. In this embodiment, after the PU film 51 is combined with the PU gel 37, the patterns 512 or the texture 513 will not disappear out due to friction or scraping. Since the waterproof layer is transparent, the pattern or texture is clear and it can be identified easily. Moreover, the transparent texture 513 can be presented as protrusion texture.

In above FIGS. 12, 13, it is found that for example, the waterproof layer 18 includes an inner layer 18 a in the fastener strips 12 made of polyester fibers and an outer layer 18 b at the outer side of the fastener strips 12. The thickness of the inner layer 18 a is over ⅓ of the fastener strips, preferably, over ½.

The difference of the present invention with the manufacturing stage disclosed in U.S. Pat. No. 6,105,214 is that in the prior art, the glued waterproof film is transferred to the backside of the fastener strip of the zipper after the waterproof film is coated with gel, or after a low hardness film is transferred to the fastener strip, it is coated on the backside of the fastener strip. Then, the PU film is adhered to the backside of the fastener strip. Then by heating, the PU gel and PU film are combined as a waterproof layer by thermal plastic stage. Therefore, in the present invention, the physical properties, such as adhesion, heat-tolerance, etc. of the single layer waterproof layer are improved so that the waterproof layer can be generated with pattern or texture. This is not disclosed by the prior art.

Effect of the present invention will be described herein. In the present invention, the PU gel is permeated into the fibers of the fastener strip so that the fastener strip is adhesive and has the function of waterproof. That is to say, when the outer PU film is destroyed by external force, the inner PU gel has the effect of waterproof. The PU gel and PU film are combined as a single film by thermal plastic stage and thus the manufacturing stage is simple and cost-efficient. The present invention can be suitable for different climate factors even boiled in water, which is also designed for preventing from yellowing and deformation. The solvent of the inner PU gel can vaporize completely so as not to harm the body. The inner texture or pattern of the waterproof layer can prevent from scraping and have the function of counterfeit-proof.

COMPARISON OF THE PRESENT INVENTION WITH PRIOR ART

In the following, the present invention is compared with a waterproof zipper adhered by thermal melting gel.

As shown in FIG. 14, the waterproof zipper of the present invention (black) and the prior art waterproof zipper (white) are used as examples. In a temperature of 100° C. and boiling in water through 30 minutes, the waterproof layer of the waterproof zipper of the present invention is retained in a good condition and the waterproof layer of the prior art waterproof zipper scraped.

Referring to FIG. 15, when the two waterproof zippers are sunk in organic solvent (ether) through 5 minutes. The waterproof layer of the waterproof zipper of the present invention is retained as the original condition, but the waterproof layer of the prior art has been scraped.

Both in physical and chemical tests, the waterproof zipper of the present invention matches the requirement of international standard.

Determination of Amines in Dyestuff

As per Adidas-Salomon A-01 requirement with reference to German test procedure for detection of carcinogenic amine in dyed materials published in German official compilation of test and inspection procedures, extracted by citrate buffered solution pH 6 at 70° C. and detected by combination of gas chromatographic-mass spectrometric (GC-MS) and this layer chromatographic (TLC) analysis. Based on German Texture method (B82.02-2 January 1998) and polyester method (B82.02-4 January 1998) Following amino material is tested:

4-Aminodiphenyl

Benzidin

4-Chlor-O-Toluidin

2-Naphthylamin

O-Aminoazotoluol

2-Amino-4-Nitrotoluol

P-Chloroanilin2,4′-Diaminoanisol(4-Methoxy-M-Phenylenediamin)

4,4′-Diaminodiphenylmethan

3,3′-Dichlorobenzidin

3,3′-Dimethoxybenzidin

3,3′-Dimethylbenzidin

3,3′-Dimethyl-4,4′Diaminodiphenylmethan

P-Kresidin(2-Methoxy-5-Methylanilin)

4,4′-Methylen-Bis-(2-Chloranilin)

4,4′-Oxydianilin

4,4′-Thiodianilin

O-Toluidin

2,4-Toluylendiamin

2,4,5-Trimethylanilin

O-Anisidine

2,4-Xylidine

2,6-Xylidine

4-Aminoazobenzene

The test result is below 5 ppm, it can assure that the minimum and maximum capacity is 30 ppm. The result is matched to the test standard.

(2) Detection by German standard test method: the heavy metal in the chromatography of the waterproof layer is lower than standard value. Tested item Test method Result Limit Sb DIN38405D 32 <1   10 ppm Cd DIN38406D 19 <0.01  0.1 ppm Pb DIN38406D 6 <0.1   1 ppm Hg DIN38406D 12 <0.01 0.02 ppm Cr DIN38406D 10 <0.1   2 ppm

Remarks: <=Less than

ppm=Parts per million

(3) Referring to German Industrial Standard (DIN53314:1996), the content of the six bond chromium by the ultraviolet ray analysis: Test component Result in ppm Limit ppm (Max) Cr ND (<0.1) 3

Remarks: ppm=Parts per million

<=Less than

ND=Not detected

(4) Referring to Japan 112 by spectrophotometer analysis to detect the content of Formaldehyde. Test component Result in ppm Limit ppm Formaldehyde <1 75 ppm

Remarks: ppm=Parts per million

<=Less than

(5) By Analysis by gas chromatography Test sample Result (ppm As Sn) Limit (ppm As Sn) Mono-butyl tin (MBT) 0.19 ppm 1 ppm

Remarks: ND=Not detected

Detection limit=0.05 ppm As Sn

ppm=Parts per million

(6) Analysis by gas chromatography Test sample Result (ppm As Sn) Limit (ppm As Sn) Di-butyl tin (DBT) 0.40 1 ppm

Remarks: ND=Not detected

Detection limit=0.05 ppm As Sn

ppm=Parts per million

(7) Analysis by gas chromatography Test sample Result (ppm As Sn) Limit (ppm As Sn) Tri-butyl tin (TBT) ND ND

Remarks: ND=Not detected

Detection limit=0.05 ppm As Sn

ppm=Parts per million

(8) (PH) Vaule detection Test sample pH value Limit PH 5.67 4.0-7.5

Result

All the test is in safety range: Item: Result: Dry containing nitrogen qualified Components of heavy metal qualified Content chromium qualified Content of Formaldehyde qualified Mono-butyl tin (MBT) qualified Contents of Di-butyl tin (DBT) qualified Contents of Tri-butyl tin (TBT) qualified PH value qualified

Although the present invention has been described with reference to the preferred embodiments, it will be understood that the invention is not limited to the details described thereof. Various substitutions and modifications have been suggested in the foregoing description, and others will occur to those of ordinary skill in the art. Therefore, all such substitutions and modifications are intended to be embraced within the scope of the invention as defined in the appended claims. 

1. A nylon waterproof zipper comprising two symmetric fastener strips; each fastener strip has a front surface and a back surface; an inner side of the front surface of each fastener strip having a cord thread protruded from the surface; two chains being mounted along the cord threads, respectively; the cord threads being fixed to the fastener strips, respectively; the two chains being engaged by a coupling slider; a back surface of each fastener strip being combined with a thin waterproof layer; characterized in that: a back surface of each fastener strip is permeated with PU gel; and then a PU film is adhered to the back surface by thermal plastic stage so as to be formed as a waterproof layer which includes an inner layer of the PU gel permeating into the fastener strips and an outer layer at an outer side of the fastener strips.
 2. The nylon waterproof zipper as claimed in claim 1, wherein the waterproof layer is formed with textures.
 3. The nylon waterproof zipper as claimed in claim 1, wherein a thickness of the inner layer is over one third of each fastener strip.
 4. The nylon waterproof zipper as claimed in claim 1, wherein a thickness of the inner layer is over one half of each fastener strip.
 5. The nylon waterproof zipper as claimed in claim 1, wherein the waterproof layer is formed with printing patterns. 